How to plan and buy out-of-home advertising: Choosing the right OOH approach for your goals and budget

Launching an out-of-home (OOH) campaign or renting a billboard involves more than choosing a location and uploading artwork. The most effective campaigns are built around clear objectives, a realistic budget, and an understanding of how OOH fits within your wider marketing strategy. Whether you’re a local business looking to drive footfall or a national brand […] The post How to plan and buy out-of-home advertising: Choosing the right OOH approach for your goals and budget appeared first on Elite Business Magazine.

Apr 22, 2026 - 08:52

How to plan and buy out-of-home advertising: Choosing the right OOH approach for your goals and budget

Launching an out-of-home (OOH) campaign or renting a billboard involves more than choosing a location and uploading artwork. The most effective campaigns are built around clear objectives, a realistic budget, and an understanding of how OOH fits within your wider marketing strategy.

Whether you’re a local business looking to drive footfall or a national brand building awareness, understanding the different ways to book out-of-home advertising space can help you choose the buying approach that best aligns with your goals.

Different OOH buying routes

When planning an OOH campaign, one of the first decisions to make is how you want to rent your advertising space. Your chosen buying model determines where your ad appears, how long it runs, and how campaign performance is measured.

When booking OOH with Alight, our planning team can guide you towards the most suitable option based on your campaign objectives and budget. In the meantime, here is a simple overview of the main buying routes available.

Choosing the right model based on your campaign goals

OOH campaigns are typically planned around one of three primary objectives: securing a fixed share of screen time, maximising the number of times your ad is played, or targeting a set number of impressions.

Fixed share of time

With fixed-time buying, your out-of-home advert is guaranteed a set percentage of display time on digital screens during specific booked intervals.

For example, a 50% share of time means your advert will play on screen for half the time the screen is live. If a screen has six ten-second advertising slots in rotation, your advert would appear in three of them.

This approach ensures consistent visibility throughout the scheduled time window. However, the exact number of impressions can vary depending on audience traffic around the site.

Fixed share of time is particularly useful for campaigns that require reliable presence during certain periods, such as local awareness campaigns or promotions near retail locations.

Guaranteed number of plays

Another option is to secure a guaranteed number of plays, which ensures your advert appears a specific number of times on the screen.

With this model, the total number of rotations is fixed. However, the timing of those plays and the number of people who see them may vary depending on audience traffic.

Guaranteed plays are often suitable for campaigns where the priority is delivering a defined volume of exposure rather than appearing at specific times.

Target number of impressions

Impression-based buying focuses on the estimated number of people who are likely to see your advert during the campaign.

Audience impressions are predicted using tools such as Route, which models traffic levels, footfall, and other location-specific factors.

While this method aims to deliver a target level of audience exposure, the exact timing of when the advert appears and the number of rotations can vary.

How out-of-home campaigns are measured

Although OOH campaigns can be bought in different ways, their performance is typically evaluated using a consistent set of industry metrics provided by Route.

These metrics help advertisers understand how many people their campaign is likely to reach and how often the advert may be seen.

Impressions

Impressions estimate the total number of times an advert is likely to be seen.

In out-of-home advertising, impressions are calculated using audience modelling data from Route, which predicts how many people pass a location and are likely to view the advert during the campaign period.

Impressions are also used to calculate CPM (Cost Per Mille), a key advertising metric that measures the cost of reaching one thousand people.

Understanding CPM can help advertisers compare the efficiency of different OOH formats and locations. Read our guide to CPM to learn more about how it works and how it’s used in OOH planning.

Reach

Reach refers to the number of unique individuals exposed to a campaign at least once.

This metric helps advertisers understand how widely their message is distributed across a target audience.

Frequency

Frequency measures how often those individuals are likely to see the advert during the campaign.

A higher frequency can help reinforce brand recognition and improve message recall.

Together, these metrics provide a clearer picture of campaign performance, regardless of whether the media was purchased based on share of time, number of plays, or impressions.